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Emergency airplane evacuations happen more often than most people think: about once every 11 days in the U.S., according to a 2000 report by the National Transportation Safety Board. Some situations are more dire than others, of course, as when the plane is on fire, but in many cases, the biggest challenge of an evacuation can be the airplane slide.

Last week at Heathrow Airport, when 136 passengers had to get off a British Airways Boeing 777 that had crashed short of the runway, they did it by escaping down the eight slides unfurled at the plane's exits. The deplaning, like the landing itself, was very successful, with no fatalities and only a handful of injuries.

The investigation won't be done for months, but it is likely that some of those injuries happened during the evacuation  not the initial crash. Even in controlled drills, accidents are common. When the new, supersized Airbus A380 underwent mandatory evacuation tests in 2006, 33 of the 873 evacuating volunteers got hurt. One suffered a broken leg, and the remaining 32 received slide burns. And that was considered a success.

So, in the unlikely event that you have to escape from a plane on an inflatable slide, here are some tips, compiled with assistance from Dan Johnson, an aviation safety expert who has worked for the airlines in various capacities for more than three decades.

1. Have a Plan: Don't wait until a flight attendant is shrieking at you to "Get out!" to decide what you're going to do. Aviation safety experts, even the most jaded ones, count the rows to their nearest exits whenever they sit down on a plane. They know that their brain will not work well under extreme duress, and their eyes will not see well in thick smoke, so they need to have a sense of their best escape routes before anything goes wrong.

2. Have Another Plan: Your fellow passengers often have trouble opening the exit hatches  it's not easy, for one thing, and even flight attendants often run into trouble. Plus, the slides malfunction more than you might expect. In the 2000 safety study, over one-third of the slide evacuations studied involved problems in the functioning of the slides. Smoke can also make your first-choice exit suddenly unusable. So instead of reading the Sky Mall catalog while you're waiting for the plane to take off, it would be wise to come up with two escape plans.

3. Get Out Fast: If all hell does break loose, remember that one of the deadliest mistakes passengers make is to lunge for their overhead luggage. This wastes precious time and clogs the aisle with obstacles. And yet, even if the cabin is full of smoke, passengers will almost invariably reach up to get their briefcases and garment bags. Video footage of emergency evacuations often shows people sailing down the slides clutching rolling suitcases. Chloe, 24, was a passenger on the British Airways flight. "I got to the door, and I realized I was holding a bamboo hat  and just thought, what am I doing rescuing a hat from a crashed plane?" she told the Coventry Telegraph.

4. Jump: Another big problem  especially among women and older passengers  happens at the top of the slide. People hesitate or try to sit down before sliding. If everyone would jump instead, as flight attendants will scream at you to do, the evacuation could go 50% faster, Johnson says. Since a fire can burn through the fuselage on an airplane in 90 seconds, faster is much, much better. When everything works right, slides are built to handle 70 passengers per minute. Many now have two lanes. To see how fast  and scary  the slide can be, check out this video of an evacuation drill off of a Boeing 777, the same kind of plane involved in the Heathrow crash landing.

5. Keep It Together: To avoid burns and unintentional cartwheels on your way down the slide, keep your heels up and your arms crossed over your chest. A lot of injuries happen when people hit the ground and sprain an ankle or break a leg because they came in out of control. Also, women should avoid wearing spiked heels and pantyhose when they fly. Pantyhose can melt onto the skin in the heat of a plane fire (as if you needed another reason not to wear pantyhose).

6. Then Get Out of the Way: Just like on the playground, the area below the slide is not a good place to hang out. If you are the first passenger out, then you should help other people get off. Otherwise, you should get out of the way. Pile-ups at the bottom of the slide can be brutal  and can also make the slide much steeper for everyone else coming down.

Congratulations! You've survived an emergency airplane evacuation. Now prepare to reflect on your experience  for hours. After an evacuation, even a successful one, passengers often have to spend hours in limbo, waiting for the authorities to release them back into civilization, often due to bureaucratic or legal paranoia. It is infuriating to passengers  and their families, who are often waiting anxiously for them  while they sit in a fluorescent-lit secure location wondering what became of the beverage cart.

So, in fact, you won't make your connection. Sorry about that. But you will have a very good story for your next seatmate, should you ever fly again.

The Unthinkable, TIME staff writer Amanda Ripley's book on human behavior in disasters, is due out in June.